Diversity of abilities

There are many reasons why people may be experiencing varying degrees of
auditory, cognitive, physical, speech, and visual disabilities. For
instance, some may have disabilities from birth, an illness, disease, or
accident, or they may develop impairments with age. Some may not
consider themselves to have disabilities even if they do experience such
functional limitations.

More about diversity of abilities

Each individual is unique. People have diverse abilities, skills, tools,
preferences, and expectations that can impact how they use the Web. For
instance, consider the following aspects:

Age-related impairments: Many people develop
age-related impairments. While they share the same functional
requirements as others with disabilities, sometimes there are
significant differences in the use of assistive technologies, the
level of computer skills, or in the use of the Web in general.

Multiple disabilities: Some people have
combinations of different kinds of disabilities, which may limit
their approaches for interacting with the Web. For example, someone
who is deaf and has low vision might benefit from captions for
audio, but only if these captions have adjustable size and color.

Health conditions: Some people have health conditions
that may affect their stamina, dexterity, or concentration. For
instance, some may experience fatigue, pain, or other symptoms that
could have an impact on their physical use of the computer or limit
the duration or extent of their use of the Web.

Changing abilities: Some people may be experiencing
progressive or recurring functional limitations that impact their
use of the Web differently at different times. For example, some
may need particular accessibility features on one day, and others or
none on another day, depending on their condition.

Temporary impairments: Some people may be
experiencing temporary impairments such as those that may occur due
to an accident, surgery, or medication. They may not know about
accessibility solutions, may not know how to use accessibility
features, and may be unaware of their needs.

Situational limitations: Some people may be
experiencing constraints due to their surrounding or due to other
situational aspects. For example, they may be in a loud environment
and unable to hear audio, in bright sunlight and unable to see a
screen, or they may not be able to afford some technologies.

Websites and web tools designed for people with a broad range of
abilities benefit everyone, including people without disabilities. It
is, therefore, important to consider the broad diversity of functional
needs rather than to categorize people according to medical
classifications.

Auditory

Auditory disabilities range from mild or moderate hearing loss in one or
both ears (“hard of hearing”) to substantial and uncorrectable hearing
loss in both ears (“deafness”). Some people with auditory disabilities
can hear sounds but sometimes not sufficiently to understand all speech,
especially when there is background noise. This can include people using
hearing aids.

More about auditory disabilities

While multimedia on the Web provides many opportunities for people with
auditory disabilities, it also poses challenges when content is not
designed to be accessible. For example, while video content can be used
to communicate information visually, audio content needs to have
alternatives, such as transcripts and captions, so that it is accessible
for people with auditory disabilities.

To use the Web effectively, people with auditory disabilities often rely
on:

Transcripts and captions of audio content, including audio-only
content and audio tracks in multimedia;

Media players that display captions and provide options to adjust
the text size and colors of captions;

Options to stop, pause, and adjust the volume of audio content
(independently of the system volume);

High-quality foreground audio that is clearly distinguishable from
any background noise.

For some people with auditory disabilities, sign language is the primary
language, and they may not read the written language as fluently.
Providing important information in sign language and using simpler text
that is supplemented by images, graphs, and other illustrations help
make web content more understandable to many people. However, it is
important to remember that not all people with auditory disabilities
know sign language.

Examples of auditory disabilities

Hard of hearing – mild or moderate hearing
impairments in one or both ears.

Deafness – substantial, uncorrectable impairment of
hearing in both ears.

Stories related to auditory disabilities

Cognitive, learning, and neurological

Cognitive, learning, and neurological disabilities involve
neurodiversity and neurological disorders, as well as behavioral and
mental health disorders that are not necessarily neurological. They may
affect any part of the nervous system and impact how well people hear,
move, see, speak, and understand information. Cognitive, learning, and
neurological disabilities do not necessarily affect the intelligence of
a person.

More about cognitive, learning, and neurological disabilities

Computer technologies and the Web provide many opportunities for people
with cognitive, learning, and neurological disabilities to interact with
content and to process information in ways that are more usable to them.
For example, people can navigate web content using different
strategies, access information in text, audio, or other formats, and
change the presentation of the content according to their individual
needs or preferences.

Depending on the individual needs, people with cognitive, learning, and
neurological disabilities often rely on:

Clearly structured content that facilitates overview and
orientation;

Consistent labeling of forms, buttons, and other content parts;

Predictable link targets, functionality, and overall interaction;

Different ways of navigating websites, such as hierarchical menu and
search;

Simpler text that is supplemented by images, graphs, and other
illustrations;

People with cognitive, learning, and neurological disabilities use
different types of web browsing methods, depending on their particular
needs. For example, some people use text-to-speech software to hear the
information while reading it visually or use captions to read the
information while hearing it. Some people use tools that resize text and
spacing or customize colors to assist reading. Others use grammar and
spelling tools to support writing. For these web browsing methods to
work, developers need to consider web accessibility requirements which
are often shared by people with hearing, physical, speech, and visual
disabilities.

Intellectual disabilities (sometimes called
“learning disabilities” in Europe and some
other countries, and “developmental disabilities” in other
regions) – involves impairments of intelligence, learning more
slowly, or difficulty understanding complex concepts. Down syndrome
is one among many different causes of intellectual disabilities.

Learning disabilities – is a functional term rather
than a medical condition, and is not uniformly defined. In Europe
and some other countries, it refers to intellectual
disabilities, while in Australia, Canada,
the U.S., and some other countries it refers to perceptual
disabilities.

Mental health disabilities – includes anxiety,
delirium, depression, paranoia, schizophrenia, and many other
disorders. These conditions may cause difficulty focusing on
information, processing information, or understanding it. In
particular medication for these disorders may have side effects
including blurred vision, hand tremors, and other impairments.

Memory impairments – involves limited short-term
memory, missing long-term memory, or limited ability to recall
language. Dementia is one among many different causes of memory
impairments.

Multiple sclerosis – causes damage to nerve cells in the
brain and spinal cord, and can affect auditory, cognitive, physical,
or visual abilities, in particular during relapses.

Neurodiversity – is a societal rather than medical term
to describe the natural diversity in neurocognitive functioning,
alike gender, ethnicity, sexual orientation, and disability.

Physical

Physical disabilities (sometimes called “motor disabilities”) include
weakness and limitations of muscular control (such as involuntary
movements including tremors, lack of coordination, or paralysis),
limitations of sensation, joint disorders (such as arthritis), pain that
impedes movement, and missing limbs.

More about physical disabilities

To use the Web, people with physical disabilities often use specialized
hardware and software such as:

Ergonomic or specially designed keyboard or mouse;

Head pointer, mouth stick, and other aids to help with typing;

On-screen keyboard with trackball, joysticks, or other pointing
devices;

Switches operated by foot, shoulder, sip-and-puff, or other
movements;

Voice recognition, eye tracking, and other approaches for hands-free
interaction.

People with physical disabilities may be using a mouse or mouse-like
device only, or keyboard or keyboard-like device only to operate the
computer. People with physical disabilities rely on keyboard support to
activate functionality provided on web pages. They may need more time to
type, click, or carry out other interaction, and they may type single
keystrokes in sequence rather than typing simultaneous keystrokes
(“chording”) to activate commands. Such keystrokes include commands for
special characters, shortcut keys, and to active menu items.

People with physical disabilities may have trouble clicking small areas
and are more likely to make mistakes in typing and clicking. Providing
large clickable areas, enough time to complete tasks, and error
correction options for forms are important design aspects. Other
important design aspects include providing visible indicators of the
current focus, and mechanisms to skip over blocks, such as over page
headers or navigation bars. People with cognitive and visual
disabilities share many of these requirements.

Examples of physical disabilities

Amputation – includes missing fingers, limbs, or other
parts of the human body.

Arthritis (previously called
“rheumatism”) – inflammation, degeneration,
or damage to the joints.

Fibromyalgia (formerly called
“rheumatism”) – the chronic pain of muscle
and connective tissues.

Rheumatism – typically refers to
arthritis and other causes of bone or joint
pain, and sometimes to fibromyalgia and
other causes for muscular and other soft tissue pain.

Reduced dexterity – is a functional term (rather
than a medical condition) that describes the ability to control the
hand, such as hand-eye coordination of people with cognitive and
neurological disabilities.

Muscular dystrophy – progressive weakness and
degeneration of muscles, sometimes including in arms and hands.

Repetitive stress injury (RSI) (also called “repetitive
motion disorder” (RMD) and “cumulative trauma disorder” (CT)) -
involves injuries to the musculoskeletal system (bones, joints,
tendons, and other connective tissues) and the nervous system from
repetitive tasks and damage.

Tremor and spasms – involuntary movement or muscle
contraction, including short twitches, and continual or rhythmic
muscle contractions.

Quadriplegia (sometimes called “tetraplegia”) -
partial or total paralysis (includes motor control and sensation) to
all four body limbs (legs and arms) and the torso.

Examples of barriers for people with physical disabilities

Websites, web browsers, and authoring tools that do not provide full
keyboard support.

Insufficient time limits to respond or to complete tasks, such as to
fill out online forms.

Controls, including links with images of text, that do not have
equivalent text alternatives.

Stories related to physical disabilities

Speech

Speech disabilities include difficulty producing speech that is
recognizable by others or by voice recognition software. For example,
the loudness or clarity of someone’s voice might be difficult to
understand.

More about speech disabilities

People with speech disabilities encounter barriers with voice-based
services, such as automated web-based hotlines and web applications that
are operated using voice commands. To use services that rely on voice,
people with speech disabilities need alternative modes of interaction
such as a text-based chat to interact with hotline representatives and
keyboard commands to operate web applications. Also, websites that
provide telephone numbers as the only means of communicating with an
organization pose barriers for people with speech disabilities.
Alternative means of communication include e-mail and feedback forms.

Examples of speech disabilities

Apraxia of speech (AOS) – includes inconsistent
articulation and production of speech sounds, and errors producing
sounds in the correct order so that spoken words or phrases become
difficult to understand.

Cluttering (also called “tachyphemia”) – includes
increased speaking rate, incorrect rhythm, intonation, and
co-articulation of sounds, and other influent speech that is
sometimes similar to stuttering.

Dysarthria – involves weakness or complete
paralysis of muscles that are necessary to produce speech, including
lips, lungs, throat, tongue, and others.

Speech sound disorder – involves difficulty or
inability to produce certain sounds or patterns of sound and
sometimes results in addition, distortion, omission, or substitution
of such sounds with others.

Stuttering – includes influent speech, repetition
of individual sounds or entire words and phrases, and misplacement
or prolongation of pauses and sounds while speaking that is
different from cluttering.

Muteness (also called “mutism”) – involves the
inability to speak due to various reasons such as anxiety, brain
injuries, or inability to hear and learn speech.

Examples of barriers for people with speech disabilities

Web-based services, including web applications, that rely on
interaction using voice only.

Websites that offer phone numbers as the only way to communicate
with the organizations.

Visual

Visual disabilities range from mild or moderate vision loss in one or
both eyes (“low vision”) to substantial and uncorrectable vision loss in
both eyes (“blindness”). Some people have reduced or lack of sensitivity
to certain colors (“color blindness”), or increased sensitivity to
bright colors. These variations in perception of colors and brightness
can be independent of the visual acuity.

More about visual disabilities

People with visual disabilities typically rely on changing the
presentation of web content into forms that are more usable for their
particular needs. For example by:

Enlarging or reducing text size and images;

Customizing settings for fonts, colors, and spacing;

Listening to text-to-speech synthesis of the content;

Listening to audio descriptions of video in multimedia;

Reading text using refreshable Braille.

For these web browsing methods to work, developers need to ensure that
the presentation of web content is independent of its underlying
structure and that the structure is correctly coded so that it can be
processed and presented in different ways by web browsers and assistive
technologies. For example, some people do not see the content and rely
on lists, headings, tables, and other page structures to be properly
coded so that they can be identified by web browsers and assistive
technologies.

Some people are only seeing small portions of the content at a time or
are perceiving the colors and design differently. Some people are using
customized fonts, colors, and spacing to make the content more readable,
or they are navigating through the content using keyboard only because
they cannot see the mouse pointer. An accessible design supports
different presentations of the web content and different ways of
interaction.

Examples of visual disabilities

Color blindness – includes difficulty
distinguishing between colors such as between red and green, or
between yellow and blue, and sometimes inability to perceive any
color.

Low vision – (in some regions also called “partial
sight”) includes poor acuity (vision that is not sharp), tunnel
vision (seeing only the middle of the visual field), central field
loss (seeing only the edges of the visual field), and clouded
vision.